<style>
    body {
        background-color: #FFFFFF;
    }
    .blue {
        background-color: #0000FF;
    }
    .yellow {
        background-color: #FFFF00;
    }
    div {
        display: inline-block;
        height: 100px;
        width: 100px;
    }
</style>
<div class="blue"></div>
<div class="yellow"></div>